After the UAV mission, I landed the UAV and kept the back pack to use the UAV in future missions (o'head picture and such); however, if I place the UAV backpack in any of the armoury cases, after the screen 'fades to black' when you restock or come back from another mission, the UAV backpack disappears; however, the UAV terminal remains.

There is no problem if you keep the UAV backpack on every mission but is some what gameplay limiting.